British Journal of Sports Medicine

British Journal of Sports Medicine

Sports and exercise medicine coming together

28-11-2019 – Malliaropoulos, N., Kaux, J.-F., Le Garrec, S., Lohrer, H.

The European College of Sports and Exercise Physicians (ECOSEP) has contributed to this issue of the BJSM, and brings together the Sports and Exercise Medicine community at the sixth ECOSEP–INSEP Congress in Paris 2019. It is really important to develop the specialty further throughout Europe and globally. Our vision is to bring Sports and Exercise Medicine Health Professionals together, increase the collaboration between Sports Medicine Centres Network, support Sports and Exercise Medicine with high-quality and innovative research, and to provide more Sports and Exercise Medicine opportunities for training. It is patients’ and athletes’ right to have the opportunity for better services through Sports and Exercise Medicine development and offering the choice to the young coming, medical students and junior doctors, generation. In this Issue Concussion is a common and high-profile injury in contact sports. The King-Devick (KD) test has been promoted as a remove-from-play sideline screening test for…

Computational methods to model complex systems in sports injury research: agent-based modelling (ABM) and systems dynamics (SD) modelling

28-11-2019 – Hulme, A., Mclean, S., Salmon, P. M., Thompson, J., Lane, B. R., Nielsen, R. O.

Introduction ‘Systems thinking’,1 2 complexity theory3 and the ‘complex systems approach’4–7 are gaining momentum among leading sports injury researchers. One reason for this is a growing recognition that traditional risk factor identification methods (eg, stepwise regression modelling) fail to reflect the complex mechanisms of sports injury causation.1 4 8 9 Effective sports injury prevention requires us to understand the complex relationships that occur among a ‘web of interacting determinants’,4 rather than try to isolate the causal effect of individual factors.1 To better understand sports injury mechanisms, researchers are exploring several different approaches. One of them—and the focus of this editorial—is using computational methods that have the potential to describe and simulate the complex and dynamic nature of sports injury causation and prevention…

The acute-to-chronic workload ratio: an inaccurate scaling index for an unnecessary normalisation process?

28-11-2019 – Lolli, L., Batterham, A. M., Hawkins, R., Kelly, D. M., Strudwick, A. J., Thorpe, R. T., Gregson, W., Atkinson, G.

Introduction  An important question for researchers and practitioners is whether an individual’s risk of injury increases if they make prior changes to their training load.1 In this field of research, ‘load’ typically refers to in-training distances covered, speed and accelerations.1 Attention has generally focused on whether a person’s acute (eg, 7 day) increase in load, normalised to that person’s prior ‘baseline’ of chronic (eg, 28 day) load, predicts injury.1 To obtain this normalised predictor, acute load is typically divided by chronic load to provide the acute-to-chronic workload ratio (ACWR).1 Fundamentally, simple ratios (Y/X) are formulated to ‘control for’ a denominator variable (eg, preceding chronic load) that is perceived to have an important biological influence on the numerator variable (eg, acute load).2 Within this notion of ‘control for’,3 it is generally posited that the denominator is a ‘nuisance’ variable…

“Implausible discussions in saturated fat research; definitive solutions wont come from another million editorials (or a million views of one)”

28-11-2019 – Nunan, D., Mellor, D., Guess, N., Lahart, I. M.

The British Journal of Sports Medicine published an opinion editorial advocating a revision of public health guidance on saturated fat.1 Here, we offer a rebuttal, incorporating evidence-based principles absent in the original editorial, focusing on the quality of the evidence presented and we discuss contradictory evidence in relation to saturated fat, low-density lipoprotein cholesterol (LDL-C), specific dietary interventions and cardiovascular disease (CVD) alongside future directions.  Effects of reducing saturated fat intake on CVD  The authors cite a 2015 ‘landmark’ meta-analysis of observational studies showing a lack of an association between saturated fat consumption and both all-cause mortality and cardiovascular outcomes.2 According to best practice evidence-based methods, these types of studies provide low-quality evidence.3 Indeed, the authors of the cited meta-analysis reported that the likelihood of the reported associations was ‘very low’,2 meaning we can have very little confidence in the…

Same label–different product: time to review the hiring criteria for therapists in sport

28-11-2019 – Smith, G. N.


Before 1988, there were no specific rules in the UK as to who could be appointed as a ‘physiotherapist’ in sport, especially professional football. Seems very strange, I know! However, in 1988, I was part of a group who recommended that therapists in professional football had to be chartered physiotherapists. A grandfather clause was also included that those already working with teams could continue, as long as they had a minimum level of qualification at diploma level. This was intended as an interim qualification to be phased out as our recommendation took effect. This was accepted and, from 1991, all members of therapy teams within English professional football had formal, objectively assessed training. The ‘grandfather clause’ then provided an educational pathway for ‘unqualified’ practitioners already working in football, who had excellent practical skills, but needed to enhance their underpinning theoretical knowledge. The recommendation was undoubtedly correct at that time…

Aerobic exercise interventions reduce blood pressure in patients after stroke or transient ischaemic attack: a systematic review and meta-analysis

28-11-2019 – Wang, C., Redgrave, J., Shafizadeh, M., Majid, A., Kilner, K., Ali, A. N.

Secondary vascular risk reduction is critical to preventing recurrent stroke. We aimed to evaluate the effect of exercise interventions on vascular risk factors and recurrent ischaemic events after stroke or transient ischaemic attack (TIA).
Intervention systematic review and meta-analysis.
Data sources
OVID MEDLINE, PubMed, The Cochrane Library, Web of Science, The National Institute for Health and Care Excellence, TRIP Database, CINAHL, Psyc
INFO, SCOPUS, UK Clinical Trials Gateway and the China National Knowledge Infrastructure were searched from 1966 to October 2017.
Eligibility criteria
Randomised controlled trials evaluating aerobic or resistance exercise interventions on vascular risk factors and recurrent ischaemic events among patients with stroke or TIA, compared with control.
Twenty studies (n=1031) were included. Exercise interventions resulted in significant reductions in systolic blood pressure (SBP) –4.30 mm Hg (95% CI –6.77 to –1.83) and diastolic blood pressure –2.58 mm Hg (95% CI –4.7 to –0.46) compared with control. Reduction in SBP was most pronounced among studies initiating exercise within 6 months of stroke or TIA (–8.46 mm Hg, 95% CI –12.18 to –4.75 vs –2.33 mm Hg, 95% CI –3.94 to –0.72), and in those incorporating an educational component (–7.81 mm Hg, 95% CI –14.34 to –1.28 vs –2.78 mm Hg, 95% CI –4.33 to –1.23). Exercise was also associated with reductions in total cholesterol (–0.27 mmol/L, 95% CI –0.54 to 0.00), but not fasting glucose or body mass index. One trial reported reductions in secondary vascular events with exercise, but was insufficiently powered.
Exercise interventions can result in clinically meaningful blood pressure reductions, particularly if initiated early and alongside education.

King-Devick concussion test performs poorly as a screening tool in elite rugby union players: a prospective cohort study of two screening tests versus a clinical reference standard

28-11-2019 – Fuller, G. W., Cross, M. J., Stokes, K. A., Kemp, S. P. T.

The King-Devick (KD) test is an objective clinical test of eye movements that has been used to screen for concussion. We characterised the accuracy of the KD test and the World Rugby Head Injury Assessment (HIA-1) screening tools as methods of off-field evaluation for concussion after a suspicious head impact event.
A prospective cohort study was performed in elite English rugby union competitions between September 2016 and May 2017. The study population comprised consecutive players identified with a head impact event with the potential to result in concussion. The KD test was administered off-field, alongside the World Rugby HIA-1 screening tool, and the results were compared with the preseason baseline. Accuracy was measured against a reference standard of confirmed concussion, based on the clinical judgement of the team doctor after serial assessments.
Results145 head injury events requiring off-field medical room screening assessments were included in the primary analysis. The KD test demonstrated a sensitivity of 60% (95% CI 49.0 to 70) and a specificity of 39% (95% CI 26 to 54) in identifying players subsequently diagnosed with concussion. Area under the receiver operating characteristic curve for prolonged KD test times was 0.51 (95% CI 0.41 to 0.61). The World Rugby HIA-1 off-field screening tool sensitivity did not differ significantly from the KD test (sensitivity 75%, 95% CI 66 to 83, P=0.08), but specificity was significantly higher (91%, 95% CI 82 to 97, P<0.001). Although combining the KD test and the World Rugby HIA-1 multimodal screening assessment achieved a significantly higher sensitivity of 93% (95% CI 86% to 97%), there was a significantly lower specificity of 33% (95% CI 21% to 48%), compared with the HIA-1 test alone.
The KD test demonstrated limited accuracy as a stand-alone remove-from-play sideline screening test for concussion. As expected with the addition of any parallel test, combination of the KD test with the HIA-1 off-field screening tool provided improved sensitivity in identifying concussion, but at the expense of markedly lower specificity. These results suggest that it is unlikely that the KD test will be incorporated into multimodal off-field screening assessments for concussion at the present time.

Temporal trends and regional variation in the rate of arthroscopic knee surgery in England: analysis of over 1.7 million procedures between 1997 and 2017. Has practice changed in response to new evidence?

28-11-2019 – Abram, S. G. F., Judge, A., Beard, D. J., Wilson, H. A., Price, A. J.

We investigated trends and regional variation in the rate of arthroscopic knee surgery performed in England from 1997–1998 to 2016–2017.
Cross-sectional study of the national hospital episode statistics (HES) for England.
All hospital episodes for patients undergoing a knee arthroscopy between 1 April 1997 and 31 March 2017 were extracted from HES by procedure code. Age and sex-standardised rates of surgery were calculated using Office for National Statistic population data as the denominator. Trends in the rate of surgery were analysed by procedure both nationally and by Clinical Commissioning Group (CCG).
A total of 1 088 872 arthroscopic partial meniscectomies (APMs), 326 600 diagnostic arthroscopies, 308 618 knee washouts and 252 885 chondroplasties were identified (1 759 467 hospital admissions; 1 447 142 patients). The rate of APM increased from a low of 51/100 000 population (95% CI 51 to 52) in 1997–1998 to a peak at 149/100 000 (95% CI 148 to 150) in 2013–2014; then, after 2014–2015, rates declined to 120/100 000 (95% CI 119 to 121) in 2016–2017. Rates of arthroscopic knee washout and diagnostic arthroscopy declined steadily from 50/100 000 (95% CI 49 to 50) and 47/100 000 (95% CI 46 to 47) respectively in 1997–1998, to 4.8/100 000 (95% CI 4.6 to 5.0) and 8.1/100 000 (95% CI 7.9 to 8.3) in 2016–2017. Rates of chondroplasty have increased from a low of 3.2/100 000 (95% CI 3.0 to 3.3) in 1997–1998 to 51/100 000 (95% CI 50.6 to 51.7) in 2016–2017. Substantial regional and age–group variation in practice was detected. In 2016–2017, between 11% (22/207) and 16% (34/207) of CCGs performed at least double the national average rate of each procedure.
Over the last 20 years, and likely in response to new evidence, rates of arthroscopic knee washout and diagnostic arthroscopy have declined by up to 90%. APM rates increased about 130% overall but have declined recently. Rates of chondroplasty increased about 15-fold. There is significant variation in practice, but the appropriate population intervention rate for these procedures remains unknown.

Altered brain microstructure in association with repetitive subconcussive head impacts and the potential protective effect of jugular vein compression: a longitudinal study of female soccer athletes

28-11-2019 – Myer, G. D., Barber Foss, K., Thomas, S., Galloway, R., DiCesare, C. A., Dudley, J., Gadd, B., Leach, J., Smith, D., Gubanich, P., Meehan III, W. P., Altaye, M., Lavin, P., Yuan, W.

To (1) quantify white matter (WM) alterations in female high school athletes during a soccer season and characterise the potential for normalisation during the off-season rest period, (2) determine the association between WM alterations and exposure to repetitive subconcussive head impacts, and (3) evaluate the efficacy of a jugular vein compression collar to prevent WM alterations associated with head impact exposure.
Diffusion tensor imaging (DTI) data were prospectively collected from high school female soccer participants (14–18 years) at up to three time points over 9 months. Head impacts were monitored using accelerometers during all practices and games. Participants were assigned to a collar (n=24) or non-collar group (n=22). The Tract-Based Spatial Statistics approach was used in the analysis of within-group longitudinal change and between-group comparisons.
DTI analyses revealed significant pre-season to post-season WM changes in the non-collar group in mean diffusivity (2.83%±2.46%), axial diffusivity (2.58%±2.34%) and radial diffusivity (3.52%±2.60%), but there was no significant change in the collar group despite similar head impact exposure. Significant correlation was found between head impact exposure and pre-season to post-season DTI changes in the non-collar group. WM changes in the non-collar group partially resolved at 3 months off-season follow-up.
Microstructural changes in WM occurred during a season of female high school soccer among athletes who did not wear the collar device. In comparison, there were no changes in players who wore the collar, suggesting a potential prophylactic effect of the collar device in preventing changes associated with repetitive head impacts. In those without collar use, the microstructural changes showed a reversal towards normal over time in the off-season follow-up period.

Infographic. The effect of protein supplementation on resistance training-induced gains in muscle mass and strength

28-11-2019 – Morton, R. W., Murphy, K. T., McKellar, S. R., Schoenfeld, B. J., Henselmans, M., Helms, E., Aragon, A. A., Devries, M. C., Banfield, L., Krieger, J. W., Phillips, S. M.

Journal Article

When you lift weights you get stronger and your muscles can get bigger, a process we call hypertrophy, and these changes can mean a big advantage in certain sports. We all ‘know’ that we need to consume supplemental protein when we lift weights to get bigger muscles, right? But what’s the real (science-based) answer? A meta-analysis is a way of looking at all of the studies that have been done in a particular area of science. In our study,1 we performed a meta-analysis of all of the published studies on the topic of protein supplementation and looked at how much extra muscle men and women gained and how much stronger they got. We found that protein supplementation did result in a greater amount of muscle gained, but not by much: about (1 pound). We also found that people got a little stronger: about a 9% boost. Protein…

More real-world trials are needed to establish if web-based physical activity interventions are effective

28-11-2019 – Vandelanotte, C., Duncan, M. J., Kolt, G. S., Caperchione, C. M., Savage, T. N., Van Itallie, A., Oldmeadow, C., Alley, S. J., Tague, R., Maeder, A. J., Rosenkranz, R. R., Mummery, W. K.

Despite the positive health benefits of physical activity, physical inactivity remains highly prevalent.1 To address this public health issue, population-based interventions that can effectively reach large numbers of people at low cost are needed.2 Numerous randomised controlled trials (RCT) have examined the effectiveness of web-based physical activity interventions, and overall, these intervention studies have found to increase participants’ physical activity levels.3 Few studies, however, have examined how well these interventions work in ‘real world’ or ecologically valid settings, where there are no repeated contacts with research staff, comprehensive assessments or incentives.4 A recent systematic review examined mobile health (m
Health) clinical trial study methodology for trials conducted in 2014 and 2015 and did not identify a single ecological trial, yet RCTs were dominant (80%, 51/71).5 To address this, we conducted two studies using the same web-based physical activity interventions: a RCT…

Any public health guidelines should always be developed from a consistent, clear evidence base

28-11-2019 – Stamatakis, E., Ding, D., Hamer, M., Bauman, A. E., Lee, I.-M., Ekelund, U.

Journal Article

We thank Chaput and colleagues1 for their comments on our recent review2 that examined the timeliness of sitting guidelines and provided a critical overview of the sedentary behaviour evidence base. To recap for the reader: we argued that evidence of sitting and health is limited and we urged caution to prevent enthusiastic but premature guideline development. Chaput and colleagues argued that the sedentary behaviour evidence base is adequate and that a provisional screen time-based benchmark is better than no benchmark at all. We see four main areas for debate and discuss them in turn. Dispute #1: ‘activity mixes’ and ‘reconceptualisation’ of physical activity in public health Initially, our respected international colleagues1 proposed that the field needs to move towards ‘activity mixes’ that take into account the 24-hour compositional nature of the physical activity, sedentary behaviour and sleep data. Consider a weekend day when…

“Is there a recent occupational paradox where highly active physically active workers die early? Or are there failures in some study methods?”

28-11-2019 – Shephard, R. J.

Journal Article

Occupational epidemiology studies in the 1980s and 1990s demonstrated a beneficial effect of physically active employment on risks of premature death,1 with HR of ~1.50 for sedentary employees (see the online supplement for a detailed discussion). However, that accepted wisdom was disputed in a recent meta-analysis which claimed that male employees faced ‘detrimental health consequences associated with high-level occupational activity, even after adjusting for relevant factors’.2 Such a view challenges existing physical activity guidelines and poses the intriguing problem why occupational activity might be bad for men but not women. Here the author scrutinises the choice of articles for this meta-analysis, the characteristics of apparently hazardous activity and potential confounding by covariates, focusing on the male data. Possible reasons why women do not show an occupational paradox are discussed in the online . Choice of articles: search strategy Articles for the meta-analysis were drawn from 13 countries, but 5 of…

Bright spots, physical activity investments that work–Gators in Motion: a holistic approach to sport-based youth development

28-11-2019 – Bopp, T., Roetert, E. P.

Programme card Country/locality/coverage: Gainesville, Florida, USA, has a population of approximately 130 000. Target population: Youth from Southeast Gainesville who are underserved, under-resourced and living in marginalised communities. What modes/types/domains of physical activity does the programme promote? Tennis is the primary sport of focus but the programme’s all-inclusive approach to physical literacy development allows for a variety of other sports and physical activities. Which of the seven best investments does the programme address? Health education. Public education. Whole-of-community approach. Sports and recreation. What sectors does it involve? Education, health, community well-being, character and life skills, and physical activity. Estimated programme reach: Gators in Motion’s parent organisation, Aces in Motion, has served over 450 youth in the Gainesville community. What is special about this programme? It integrates academic enrichment, character and life…

Education from other sports medicine journals #11

28-11-2019 – Kearney, R., Le, C. Y., Heerey, J., OCallaghan, A.

Exercise more or sit less? A randomized trial assessing the feasibility of two advice-based interventions in obese inactive adults
J Sci Med Sport. 2018; 21:708–713 Have you ever considered that sitting is doing you harm? Prolonged inactivity has been linked with many diseases including cardiovascular disease and type 2 diabetes. Sitting less and exercising more is easier said than done. Increasing the amount of exercise one does can be challenging for a number of reasons. So, do other strategies exist for reducing sedentary behaviour and are they effective? This randomised controlled trial compared an intervention aiming to increase moderate to vigorous intensity exercise (Ex
More—increase moderate to vigorous activity to at least 30 min per day) against decreasing sedentary time (Sit
Less—reduce sitting time) in inactive obese people. The results revealed improvements in activity time and reduced sedentary time in the Ex
More and Sit
Less groups as expected. Interestingly both groups had…

Before and after major neck surgery

28-11-2019 – Della Villa, S.

Sporty beginnings I have always loved sport, and I entered into the sports medicine environment for this reason. During my life I have enjoyed swimming, skiing, running, tennis and football, and I have always tried to fit as many of these activities around my family and work commitments as possible. From a career perspective I was lucky enough to work with the San Francisco 49ers at a young age, before having a wonderful experience working as a sports physician in a Bologna during the next stage of my career. The biggest joy of my professional life was bringing the football medicine community together in recent years via the isokinetic conferences. In short, I love sport and it has played a major part in my life. Doctor-turned-patient I was very fortunate in that for a long time I had never experienced anything close to a serious pathology….